Hong Kong -LRB- CNN -RRB- -- Panasonic halted operations at three factories in China after angry protesters ransacked Japanese businesses over the weekend amid rising tensions over disputed islands in the East China Sea .

Violence against Japanese companies was seen in Xi'an , Dongguan , Changsha and Guangzhou , according to local media reports . A Panasonic factory was set on fire and a Toyota dealership in Qingdao were damaged on Saturday , and a Jusco department store was ransacked . In Guangzhou , demonstrators broke into the Garden Hotel and attacked a Japanese restaurant on the second floor , according to the South China Morning Press .

Panasonic has suspended work at three plants in China until Tuesday , after factories in Qingdao and Suzhou were damaged by protesters , company officials told CNN . Panasonic also halted operations at a factory in Guangdong province until Tuesday as some local employees staged a strike as protest against Japan 's claim to the island chain , called Diaoyu by China and Senkaku by Japan .

Background : How remote rock split China , Japan

A Heiwado Co. department store in Changsha was ransacked , as were Japanese supermarkets in several cities , Japan 's Kyodo News Service reported .

`` The Sino-Japanese economic war has officially begun , '' Chinese economist Wang Fuzhong wrote on Weibo , a Chinese microblogging site . `` I hope it wo n't end in a situation where everyone loses . ''

The Japan tourism industry , which has been struggling after the 2011 Tohoku earthquake and tsunami , is being hit by the dispute , after calls in China for tourists to stop visiting Japan . The head of a hotel at the foot of Mount Fuji told CNN that cancellations from Chinese tourists -- which make up `` about 30 % to 40 % '' of his business -- are stacking up . `` China is a big market for us , it would be very damaging for us to see a decline of the Chinese tourists , '' said the man , who gave his surname as Watanabe .

A Chinese tour guide on the streets of Ginza shopping district in Tokyo told CNN that in the six years she 's worked in Japan this situation `` is the worst of her career . ''

`` I do not expect much of the tours -LRB- from China -RRB- coming back from now . Most of tours were cancelled , '' said the guide , who asked CNN to use her Japanese name Mitsu Matsumoto for fear of reprisals .

`` I want them -LRB- China and Japan -RRB- to be friendly again . Otherwise tour agents are going to bankrupt and tour guides like us will be affected badly , '' Matsumoto said . `` I wish the issue will be solved soon . ''

Chinese state media , reporting on the protests , decried the violence . Even hawkish publications , such as Global Times -- which ran an editorial `` Discard illusion of friendly ties with Japan '' last week -- published an editorial Monday headlined `` Violence is never appropriate solution . ''

Meanwhile , an editorial in the China Daily on Monday called on China to impose economic sanctions against Japan . `` Taking a cue from the U.S. practice , China can use the security exception clause to reduce the export of some important materials to Japan , '' the editorial said .

On Thursday last week a Chinese official warned that Tokyo 's move to `` buy '' a disputed island chain in the East China Sea would hurt trade between Asia 's two largest economies . The battle over ownership of the island chain will `` inevitably '' have a negative impact on Sino-Japan economic ties , Vice Minister of Commerce Jiang Zengwei said Thursday , state-run Xinhua reported .

The islands sit among popular fishing waters and are also believed to be rich in oil resources . Ownership of the chain would allow exclusive commercial rights to the seas surrounding the islands .

Despite booming auto sales in China , sales of Japanese car brands are down 2 % in China compared to a year ago , according to the China Association of Automobile Manufacturers . Meanwhile , sales of car brands from other foreign countries , including Germany , the U.S. , South Korea and France , are up 25 % , 19 % , 12 % and 4 % respectively .

Luo Lei , deputy secretary-general of China Automobile Dealers Association , said earlier this week that Toyota purchases have fallen 15 % while Mazda sales are down 6 % year over year .

Tensions between China and Japan -- the world 's second and third largest economies , respectively -- escalated on Friday as Chinese surveillance vessels entered the disputed area to begin patrols and `` law enforcement , '' according to Chinese state-run media .

China dispatched the ships after the Japanese government bought several of the islands from a private Japanese owner last week .

The Chinese vessels entered Japan 's territorial waters despite warnings from the Japanese Coast Guard , said Shinichi Gega , a spokesman for Japan 's 11th Regional Coast Guard Headquarters .

Japanese Prime Minister Yoshihiko Noda said Tokyo would `` take all possible measures to ensure security '' of the islands , located between Okinawa and Taiwan .

China is Japan 's largest trading partner . Nearly 20 % of Japanese exports last year were sold to mainland China , compared to 15.3 % exported to the U.S. , according to figures from the Japan External Trade Organization .

Last week , the Japanese government approved the purchase for 2.05 billion yen -LRB- $ 26.2 million -RRB- the group of small islands from the Kurihara family , a private Japanese owner , according to Chief Cabinet Secretary Osamu Fujimura .

China says its claim to the islands goes back hundreds of years . Japan formally recognized them as Japanese sovereign territory in 1895 .

The islands were administered by the U.S. occupation force after World War II . But in 1972 , Washington returned them to Japan as part of its withdrawal from Okinawa .

CNNs Junko Ogura and Yoko Wakatsuki in Tokyo and C.Y. Xu in Beijing contributed to this report

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Panasonic halted operations at three factories in China after violent protests

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Protesters ransacked Japanese businesses and damaged Japanese vehicles

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Panasonic reported two plants were damaged by weekend anti-Japan protesters

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Chinese economist : `` The Sino-Japanese economic war has officially begun ''